Does jigglypuffs up special (sing) make oppenents sleep on the edge or air?

Question

all in the title

Answer 1

Jiggly's Up Special will put opponents into a sleep state when the opponent(s) is on the ground only.

It has no effect in the air to the opponents.
If used offstage, it usually means an early death for Jiggly.
On the edge, the opponent is immune to Jiggly's Sing.

Source: Experience (and dying multiple times)

Answer 2

Jigglypuff's Sing attack only works if the opponents are in range, but does not work on airborne foes.

Source:http://bulbapedia.bulbagarden.net/wiki/Jigglypuff_(Super_Smash_Bros.)